Apparatus for fabricating a III-V nitride film and a method for fabricating the same

Abstract

A hydrogen chloride gas and an ammonia gas are introduced with a carrier gas into a reactor in which a substrate and at least an aluminum metallic material through conduits. Then, the hydrogen gas and the ammonia gas are heated by heaters, and thus, a III–V nitride film including at least Al element is epitaxially grown on the substrate by using a Hydride Vapor Phase Epitaxy method.The whole of the reactor is made of an aluminum nitride material which does not suffer from the corrosion of an aluminum chloride gas generated by the reaction of an aluminum metallic material with a hydrogen chloride gas.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]This invention relates to an apparatus and a method for epitaxial growth of a III–V nitride film including at least Al element on a substrate by using a Hydride Vapor Phase Epitaxy (HVPE) method.[0003]2. Related Art Statement[0004]In opto-electronic device such as light-emitting diodes and laser diodes, it is proposed that a III–V nitride film having a composition of AlxGayInzN (X+Y+Z=1) including at least Al element is epitaxially grown on a given substrate. For example, it is described in “J. Appl. Phys., 68, No. 7 (1999)”, from pp774 onward that a GaN film is epitaxially grown on a sapphire substrate.[0005]In this method, a Ga metallic material is charged into a reactor in which a sapphire substrate having a GaN film on its surface is held, and a hydrochloric gas is also introduced into the reactor to generate a gallium chloride gas. Then, the gallium chloride gas and an ammonia gas are reacted with each other to dep...

AI Technical Summary

Benefits of technology

[0017]In the first fabricating apparatus, the whole of the reactor may be made of aluminum nitride material in fabricating a III–V nitride film including at least Al element. Moreover, the reactor body may be made of silicon oxide and an AlN film may be coated on the inner surface of the reactor body to complete the reactor to be used in the present invention. In both cases, the reactor is not corroded by the AlCl gas. In the former case, the AlN film can be fabricated by a thermal CVD method. Therefore, the reactor body can be coated by the AlN film without corrosion.

[0018]Moreover, in the first fabricating apparatus, the part of the reactor to be contacted with the AlCl gas may be made of aluminum nitride material, and the rest may be made of silicon oxide-based material to complete a hybrid reactor made of the aluminum nitride and the silicon oxide material. In this case, the thus obtained hybrid reactor is partially made of the silicon oxide-based material to be easily processed, and thus, the fabricating cost of the reactor can be decreased.

[0024]According to the above first fabricating apparatus and the second fabricating apparatus, the III–V nitride film can be epitaxially grown on a given substrate at a high growth rate with the removal or the mitigation of the AlCl gas corrosion, so that the properties of the III–V nitride film can be developed.

Problems solved by technology

It is confirmed, however, that the AlN film with good and stable properties cannot be fabricated using the above conventional HVPE method.

However, the silicon oxide-based material is likely to be corroded by an aluminum chloride gas generated through the reaction of an aluminum metallic material and a chloride-based gas to form pinholes in the reactor.

Such a poor crystallinity AlN film can not be used for an opto-electronic device substrate.

Moreover, if the pinholes are formed in the reactor through the corrosion of the AlCl gas, various gases are leaked from the reactor to the outside to bring pollution to the outer environment, in addition to the problem that the surrounding air is introduced into the reactor.

However, such an anti-corrosion material shows only poor processing performance, and thus, can not be employed practically.

Moreover, the anti-corrosion material is expensive, resulting in the higher cost of the A&N film.

The above problems due to the conventional HVPE method exist in fabricating a AlxGayInzN (X+Y+Z=1), in addition to the above AlN film.

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